The brightest possible composition

[dangerousamateur]

Hi,

 

I'm looking for the brightest possible pyrotechnical formula.

NaNO3 + Mg or MgAl seems to be a killer, but is there something brighter?

 

Color is not important.

[Potassiumchlorate]

Potassium perchlorate+cryolite+Mg should be a bit brighter. Or maybe ammonium perchlorate+cryolite+dichromated Mg.

[AdmiralDonSnider]

I think there has been a vid of a barium nitrate based torch comp, pretty old-fashioned, that was really bright. Use the search.

[a_bab]

I've seen some note about adding oxalic acid to a regular flash compo - it will make the flash very bright (5% IIRC).

 

In terms of light output the good old barium nitrate/Al based compos are the brightest.

[stckmndn]

I haven't run across anything more obnoxiously brighter than Indy Red. Is there an Indy White?

[Potassiumchlorate]

Are we talking about a flare or a flash composition? Potassium perchlorate/Mg 50:50 is pretty unbeatable.

[AdmiralDonSnider]

As he mentions "battlefield illumination" I assume we talk about either parachute based or hand-held flare candles.

[optimus]

Barium Flouride?

[californiapyro]

here are two of my favorites:

 

my own composition:

 

Strontium Nitrate 53

Magnesium 31

PVC or Parlon 16

 

http://www.youtube.com/watch?v=GR8uKKZ31Ko

 

 

 

 

and just 50:50 kno3:coarse MG

 

http://www.youtube.com/watch?v=_qFGR5GSS44

 

[Potassiumchlorate]

I love your red one. It's similar to Bleser's Red Mg though with 3% more Mg in it.

 

The highest light output is probably in a white or yellow composition, though.

[optimus]

Barium Flouride?

 

I'm sure I've seen flare formulas using this but nothing is coming up after a quick search.

 

There are quite a few topics on rec.pyro that discuss super-bright flares, this might be of interest:

 

Flare 1 Flare 2 Flare 3

Ba light Na light I Na light II

--------------------------------------------------------------

Ba(NO3)2 50

NaNO3 50 40

Mg (40 mesh) 50 50 60

Polyester +3-5 +3-5 +3-5

Spec.grav(g/cc) 1.8 1.45 1.3

Burn rate(mm/s) 4.0 5.0 6.4

Intensity(cd/cm)8000 14,000 28,000

Energy(cd.s/g) 11,000 18,000 24,000

[Mumbles]

I don't know if I've seen any formulas that specifically use barium fluoride as a component. It does bring to mind the MTV flare consisting of magnesium, teflon, and viton ( a fluorinated binder) which produces magnesium fluoride as a product along with plenty of free carbon. It's prepared in a 60:35:5 proportion, and actually rather sensitive to most forms of ignition.

 

Another thing that comes to mind are compositions containing fine titanium, zirconium, or hafnium (in increasing order of brightness).

[dangerousamateur]

Thanks for your suggestions.

 

I meant flares, not flash. And please ignore very special/expensive stuff like Barium Flouride, Teflon, zirconium ect.

 

Barium/potassium nitrate is not so critical, but how do you deal with sodium nitrate and Mg?

 

I don't have dichromate for coating and it's to toxic for me.

I just made some red stars with strontium nitrate (what I assume to be about as hygroscopic as sodium nitrate), dextrine bound, and the simply don't dry completely, even after a week.

 

Can I use PVC as a binder? Any experince with that?

 

 

 

And then I had the problem before that when I stuff flares in paper tubes, the tube/it's ashes does block the light output to the sides.

On the other hand, without a cover the composition will quickly engulf along it's surface and burn to fast. Aluminium tubes seem to be a solution, but they are to expensive.

 

 

edit:

And have you got any experience swapping magnalium in for the magnesium?

Even if I use acetone or alcohol binders, the solvent still has some water in it. I would really prefer working with MgAl here.

 

How much performance will I sacrifice this way?

Edited May 9, 2012 by dangerousamateur

[Potassiumchlorate]

Sodium nitrate is more hygroscopic than strontium nitrate, though the strontium salt is pretty hygroscopic too.

 

I have made Electric Magenta stars bound with dextrin, and they are still fine after more than two years, but I keep them in small plastic medicin bottles.

 

When I bind with alcohol I use isopropanol, after a suggestion by some guys here on the board. It's 99.5% alcohol. Works fine for organic Bengals with shellac.

 

When using acetone as a solvent, some magnesium is consumed by the small amount of water in the acetone, but most of the magnesium will be fine, if you do it in a place with a pretty low air humidity. It's preferrably done on cold winterdays or hot summerdays; in the shadow in the latter case.

[PersonGuyDude]

If you just want a REALLY bright ground device magnesium turnings, even in the open (and mixed with a oxidizer) will be more than bright enough, and cheap!

 

Obviously for stars and such you will want some kind of metallic color or flare composition. A mixture of fine and coarse Ti is crazy bright in any star composition as well

[al93535]

I wanted an insanely bright torch, after lots of testing I found two:

 

I pressed my comp into a 2" diameter by 4" long tube made with two wraps of 70lb kraft, this way the tube burns away with the comp. Its easy to press into the paper tube using a PVC pipe as a form, then slide the pressed device out afterwards.

I did use an ignition comp on top, which consisted of BP (scratch mix) with +15% -325 mgal.

I liked the Barium nitrate based formula best as it had a pleasing white light as compared to the yellow from the sodium. I cant say which was actually brighter though.

Massage the mineral oil into the oxidizer then add the screened fuels to the mix and kneed by hand. This protects against moisture and makes pressing pain free!

 

Barium nitrate 55

sulfur 4

10890 (or any american dark flake al)18

mxd 120 aluminum (or any about 50 micron spherical al) 13

-100+200 atomized magnesium 8

Mineral oil 2

 

Sodium nitrate 34

granular magnesium -200 +325 mesh coated with linseed oil 14

-100+200 atomized magnesium 50

mineral oil 2

[Potassiumchlorate]

That barium nitrate one seems great. I have some 40µm Mg that might make it even brighter. Can this be pressed by hand or do you need a hydraulic press?

[dangerousamateur]

Considering compacting those mixtures - they are kind of flashpowder like... I guess ramming is a bad idea or what do you think?

Can this be pressed by hand

This would be my only solution too...

 

 

 

And in theory, what will be brighter - magnesium or magnalium?

Since it is more pleasant to work with, I prefer magnalium of course, but how about performance?

[al93535]

You can press by hand, however the burn rate will increase and may be a bit erratic. The oil facilitates a very easy to press mix. Traditionally aluminum has always made the brightest torch, which is why the military likes it. So I would assume that magnalium would indeed be brighter.

[Peret]

A compound of magnesium with barium nitrate will be the brightest. In the absence of a chlorine donor, one of the main combustion products is incandescent barium oxide, which is a strong white emitter even without the added metal. Aluminum and magnalium are almost as bright because of the extremely high temperature of the flame, but 60% barium nitrate - 40% magnesium is the brightest you can get with commonly available chemicals. Anything containing carbon in the mixture will reduce the brightness. I can't find any warnings against ramming it - Shimizu says, "Barium nitrate alone cannot be ignited or caused to explode even by a strong impact". I'd still be a bit cautious about hammering on a mixture with finely powdered metal.

[al93535]

I thought we were discussing only flares, after looking at the title it does indeed say brightest composition.

 

In that circumstance magnesium and barium nitrate will provide the brightest light per unit of weight. Say for a gram of flash, it will outperform a gram of flash which had used aluminum powder.

 

However, for flares this is not true. Flares do not consume all their composition instantly, so now we have a volume factor. Magnesium is somewhere about 2/3 as dense as aluminum. So when used in a flare, the same weight of aluminum based composition will take up less volume, therefore more material will burn and will emit more radiation and be brighter then the magnesium based counterpart. (with equal diameter flares of course)

 

Then of course you have what kind of powders are used, and for flares atomized powders are denser, and thus is why I used them.

 

In addition, another determining factor in brightness will be burn speed, and pressure used to consolidate the composition.

 

So it ll depends on how the brightest composition will be utilized....

[dangerousamateur]

Nono, no flash, just flares.

 

Magnesium is somewhere about 2/3 as dense as aluminum. So when used in a flare, the same weight of aluminum based composition will take up less volume, therefore more material will burn and will emit more radiation and be brighter then the magnesium based counterpart. (with equal diameter flares of course)

 

Thats unfair. I would compare 10g of A with 10g of B, no matter how big the volume is.

And the burning speed does not matter, it can be regulated somehow.

 

 

Lets formulate it this way:

10g of composition gives that much of radiation energy inside the visible spectra.

[Potassiumchlorate]

Barium nitrate and magnesium feels superior to anything else.

[Potassiumchlorate]

But I was wrong. Dr. Shimizu found out that 40% sodium nitrate and 60% magnesium gives a light intensity of 28000 candela/cm, whereas 50% barium nitrate and 50% magnesium "only" gives 8000. The light energy is 24000 and 11000 candela*sec/gram respectively. Fireworks the Art Science and Technique, p. 225.

 

If you find white "brighter" than yellow, it is still scientifically so that yellow is brighter.

[val77]

Source: Kirk-Otthmer chemical encyclopedia[8]. Chapter 'Explosives and Propellants'.

Comments: Heat of reaction: 8.989 kJ/g, Gas volume: 15 cm3/g, ignition temperature: 700°C,

impact sensitivity test: 26% of TNT. half a pound of this flash delivers 120 million candlepowder.

It is used in the M120A1 and M112A1 flare cartdriges.

Preparation:

 

Aluminum (20 micron; atomized)....................40

Potassium perchlorate (24 micron).................30

Barium nitrate (150 micron).......................30

 

HA